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Turkish police detained 11 foreigners suspected of being members of an Islamic State cell in Istanbul linked to the suicide bombers who staged the attack this week at Istanbul's main airport, broadcaster Haberturk said on its website on Friday.

The arrests in the dawn raid, by a counter-terror police squad in the Basaksehir district on the European side of the city, brought the number of people detained in the investigation to 24, it said.

A police spokesman could not confirm the report, which was also carried by other media.

Three suspected Islamic State suicide bombers killed 44 people in a gun and bomb attack at Istanbul's main airport on Tuesday, the deadliest in a string of attacks in Turkey this year.

The suspected suicide bombers were Russian, Uzbek and Kyrgyz nationals, a Turkish government official said on Thursday.

Separately, security forces on Wednesday detained four Turkish citizens at the Oncupinar border gate in southeast Turkey on suspicion of membership in a terrorist group, the local governor's office said in a statement.

The four were attempting to return to Turkey from a conflict zone in Syria under Islamic State control, it said.